Cisco CRS-1 System Description page 66

OC-48 Packet Over SONET/Dynamic Packet Transport PLIMs
OC-192 interfaces and provides Layer 1 and Layer 2 interface capabilities, for 16 separate OC-48 data streams,
by removing and adding the proper Layer 1 and Layer 2 header information as data packets enter and exit the
PLIM. The 16xOC-48 PLIM feeds the MSC with one 40 Gbps data packet stream.
The following table describes the features of the 16xOC-48 PLIM.
Table 8: Features of the 16xOC-48 PLIM
Feature
Optics modules
Framers
DPT or transparent mode
components
Physical interface
controller
Additional components
The Cisco IOS XR software also provides loopback and diagnostic functions for the 16xOC-48 PLIM.
Cisco CRS Carrier Routing System 8-Slot Line Card Chassis Enhanced Router System Description
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Description
Provide the receive (RX) and transmit (TX) optic interfaces for each of the 16
ports. The 16xOC-48 PLIM uses small form-factor pluggable (SFP) optics
modules that can be removed and replaced in the field while the PLIM is powered
up. The SFPs provide the 16xOC-48 PLIM with the ability to support short-reach
(SR), intermediate-reach (IR), and long-reach (LR) optics on any port.
Provide processing and termination for SONET Section, Line, and Path layers.
This includes alarm processing and APS support and management. The framer
supports both packet and cell processing for a multiservice operating mode.
Provide the MAC layer function for the Spatial Reuse Protocol used in the DPT
mode. When the 16xOC-48 PLIM operates in the POS mode, these components
operate in the transparent mode.
Provides data packet buffering and Layer 2 processing and multiplexing and
demultiplexing of the 16 OC-48 data streams. This includes processing for VLANs
and back-pressure signals from the MSC.
Provide power, clocking, voltage and temperature sensing, and an identification
EEPROM that stores initial configuration information and details about the PLIM
type and hardware revision.
Line Cards and Physical Layer Interface Modules Overview